diff --git a/Lib/test/test_pep277.py b/Lib/test/test_pep277.py
index f1b7a59..a5f6303 100644
--- a/Lib/test/test_pep277.py
+++ b/Lib/test/test_pep277.py
@@ -5,22 +5,22 @@
 from test import support
 
 filenames = [
-    'abc',
-    'ascii',
-    'Gr\xfc\xdf-Gott',
-    '\u0393\u03b5\u03b9\u03ac-\u03c3\u03b1\u03c2',
-    '\u0417\u0434\u0440\u0430\u0432\u0441\u0442\u0432\u0443\u0439\u0442\u0435',
-    '\u306b\u307d\u3093',
-    '\u05d4\u05e9\u05e7\u05e6\u05e5\u05e1',
-    '\u66e8\u66e9\u66eb',
-    '\u66e8\u05e9\u3093\u0434\u0393\xdf',
+    '1_abc',
+    '2_ascii',
+    '3_Gr\xfc\xdf-Gott',
+    '4_\u0393\u03b5\u03b9\u03ac-\u03c3\u03b1\u03c2',
+    '5_\u0417\u0434\u0440\u0430\u0432\u0441\u0442\u0432\u0443\u0439\u0442\u0435',
+    '6_\u306b\u307d\u3093',
+    '7_\u05d4\u05e9\u05e7\u05e6\u05e5\u05e1',
+    '8_\u66e8\u66e9\u66eb',
+    '9_\u66e8\u05e9\u3093\u0434\u0393\xdf',
     # Specific code points: fn, NFC(fn) and NFKC(fn) all differents
-    '\u1fee\u1ffd',
+    '10_\u1fee\u1ffd',
     # Specific code points: NFC(fn), NFD(fn), NFKC(fn) and NFKD(fn) all differents
-    '\u0385\u03d3\u03d4',
-    '\u00a8\u0301\u03d2\u0301\u03d2\u0308',     # == NFD('\u0385\u03d3\u03d4')
-    '\u0020\u0308\u0301\u038e\u03ab',           # == NFKC('\u0385\u03d3\u03d4')
-    '\u1e9b\u1fc1\u1fcd\u1fce\u1fcf\u1fdd\u1fde\u1fdf\u1fed',
+    '11_\u0385\u03d3\u03d4',
+    '12_\u00a8\u0301\u03d2\u0301\u03d2\u0308', # == NFD('\u0385\u03d3\u03d4')
+    '13_\u0020\u0308\u0301\u038e\u03ab',       # == NFKC('\u0385\u03d3\u03d4')
+    '14_\u1e9b\u1fc1\u1fcd\u1fce\u1fcf\u1fdd\u1fde\u1fdf\u1fed',
     ]
 
 # Mac OS X decomposes Unicode names, using Normal Form D.
@@ -32,11 +32,11 @@
 if sys.platform != 'darwin':
     filenames.extend([
         # Specific code points: fn, NFC(fn) and NFKC(fn) all differents
-        '\u1fee\u1ffd\ufad1',
-        '\u2000\u2000\u2000A',
-        '\u2001\u2001\u2001A',
-        '\u2003\u2003\u2003A',  # == NFC('\u2001\u2001\u2001A')
-        '\u0020\u0020\u0020A',  # '\u0020' == ' ' == NFKC('\u2000') ==
+        '15_\u1fee\u1ffd\ufad1',
+        '16_\u2000\u2000\u2000A',
+        '17_\u2001\u2001\u2001A',
+        '18_\u2003\u2003\u2003A',  # == NFC('\u2001\u2001\u2001A')
+        '19_\u0020\u0020\u0020A',  # '\u0020' == ' ' == NFKC('\u2000') ==
                                 #  NFKC('\u2001') == NFKC('\u2003')
 ])